If they insist of having an equestrian phase, it could be interesting to replace show jumping with a basic dressage test for a couple of reasons. 1) It requires a calm and gentle approach, and you're not able to just gallop through the course and hope the horse saves your skin, 2) the horse's level of relaxation directly impacts the marks, 3) it arguably requires a higher base level of riding skill, and 4) there is less danger of injury for both horse and rider.
If they're going to put relatively unexperienced riders on horses they shouldn't be allowed spurs at all, just as would be the case outside of the olympics, and they really should be able to build some kind of relationship with the horses on the ground and in the saddle before the competition. It's outrageous that the same horses are used multiple times too. The FEI should absolutely be involved to set some better welfare standards, because from the outside it looks like the event has been arranged by people who don't know much at all about horses or the equestrian sport, particularly at higher levels